1. Field of the Invention
The present invention relates to a track and hold sampling circuit.
2. Background Art
A traditional track and hold circuit generally comprises an input buffer circuit, a current switch, a drive transistor and a sampling capacitor. As a traditional track and hold circuit stays in holding phase, sampling signals of upper electrode plate and input signals are isolated by OFF-state drive transistor, resulting to an undesirably strong sample-and-hold coupling in sample capacitors and input signals. In addition, in hold phase, the drive transistor in a sampling switch starts to work in a linear region, in a way that greatly reduces switching speed of the current switch.